A sound wave in air is illustrated below.

Points A, B, C and D are all the centers of regions of compression in the sound wave.
Describe what happens as one complete sound wave moves past a point.

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The particles in the air are disturbed by the sound waves and vibrates to and fro, in a direction parallel to the direction of the sound waves.
An air particle in the sound wave will vibrate from its rest position to the left, until it reaches its maximum displacement to the left, then vibrate towards the right, move past its rest position, until it reaches its maximum displacement to the right. Then it vibrates to the left, until it returns back to its original rest position to complete one wave motion of the sound wave.